New observations from the Event Horizon Telescope (EHT) reveal a significant and unexpected change in the supermassive black hole at the center of galaxy M87. Data collected over four years shows that the magnetic field surrounding the black hole has completely reversed its direction, a discovery that challenges current scientific models of black hole behavior.
These findings, based on images of the first black hole ever directly observed by humanity, provide a deeper look into the dynamic and turbulent environment near a black hole's event horizon. The observations also offer the first clear view of the base of the powerful jet of matter erupting from the black hole's vicinity.
Key Takeaways
- The magnetic field around the black hole M87* flipped its polarization direction between 2017 and 2021.
- This reversal was described by researchers as "totally unexpected" and forces a re-evaluation of theoretical models.
- Despite the magnetic flip, the size of the black hole's shadow remained consistent, aligning with Einstein's theory of general relativity.
- For the first time, astronomers have clearly linked the base of the black hole's energetic jet to the glowing ring of plasma around it.
- The addition of new telescopes to the EHT network resulted in sharper, more detailed images in the latest observations.
A Surprising Magnetic Reversal
The Event Horizon Telescope collaboration has released new imagery of M87*, the supermassive black hole located approximately 55 million light-years from Earth. The data shows a dramatic shift in the structure of the magnetic fields encircling the black hole over a four-year period.
Observations from 2017 depicted the polarized light from the superheated gas, or plasma, swirling in one direction. By 2021, the pattern had completely reversed. This discovery suggests the environment immediately outside the event horizon is far more chaotic than previously thought.
"The fact that the polarization pattern flipped direction from 2017 to 2021 was totally unexpected," stated EHT team member Jongho Park, a researcher at Kyunghee University. "It challenges our models and shows there’s much we still don’t understand near the event horizon."
The cause of this magnetic reversal is not yet clear. Researchers speculate it could be a result of the magnetic structure within the plasma interacting with material being pulled into the black hole.
M87* by the Numbers
- Mass: 6.5 billion times the mass of our sun.
- Distance: 55 million light-years from Earth.
- Location: Center of the Messier 87 (M87) galaxy.
A Stable Shadow in a Dynamic Environment
While the magnetic field showed significant change, one key aspect of the black hole remained constant. The size of the dark central region, known as the black hole's shadow, was consistent across all observations. This stability provides strong confirmation of predictions made by Einstein's theory of general relativity.
This contrast between a stable shadow and a fluctuating magnetic field highlights the complexity of the physics at play. It indicates that while the black hole's fundamental properties are stable, the material orbiting it is subject to intense and unpredictable forces.
"What’s remarkable is that, while the ring size has remained consistent over the years... the polarization pattern changes significantly," said team co-leader Paul Tiede, an astronomer at the Center for Astrophysics | Harvard & Smithsonian. "This tells us that the magnetized plasma swirling near the event horizon is far from static; it's dynamic and complex, pushing our theoretical models to the limit."
First View of the Jet's Base
The new, higher-resolution images have also provided an unprecedented view of the powerful jet of particles being ejected from M87*. For the first time, scientists could clearly see the base of this jet and its connection to the bright ring of plasma surrounding the black hole.
Supermassive black holes are known to launch these jets at nearly the speed of light. They are powerful enough to influence the evolution of their entire host galaxy by injecting vast amounts of energy into the surrounding space. Understanding how these jets form is a major goal in astrophysics.
Why Jets Matter
Jets are streams of ionized matter ejected from the poles of black holes. They are channeled by powerful magnetic fields and can extend for thousands of light-years. By studying their origin, scientists can better understand how black holes feed and how they impact star formation and galactic structure.
Observing the direct link between the accretion disk—the swirling ring of matter—and the jet provides crucial data for refining models of this phenomenon. It helps confirm that the energy powering the jet originates from the material orbiting just outside the event horizon.
An Evolving Global Telescope
The improved quality of the 2021 images is a direct result of the expansion of the Event Horizon Telescope network. The EHT is not a single telescope but a global array of radio telescopes that work together to create a virtual, Earth-sized observatory.
For the latest observation campaign, two new facilities were added to the network: the Kitt Peak Telescope in Arizona and the NOEMA (Northern Extended Millimeter Array) in France. Their inclusion significantly boosted the EHT's sensitivity and resolution.
Mariafelicia De Laurentis, an astronomer at the University of Naples Federico II in Italy, commented on the project's progress. "These results show how the EHT is evolving into a fully fledged scientific observatory, capable not only of delivering unprecedented images, but of building a progressive and coherent understanding of black hole physics," she said.
Future upgrades are already planned for other telescopes in the network, including the Greenland Telescope and the James Clerk Maxwell Telescope. These enhancements promise even more detailed views of black holes and the extreme physics that govern them.
